var wordPattern = function(pattern, s) {
    const word2ch = new Map();
    const ch2word = new Map();
    const words = s.split(' ');
    if (pattern.length !== words.length) {
        return false;
    }
    for (const [i, word] of words.entries()) {
        const ch = pattern[i];
        if (word2ch.has(word) && word2ch.get(word) != ch || ch2word.has(ch) && ch2word.get(ch) !== word) {
            return false;
        }
        word2ch.set(word, ch);
        ch2word.set(ch, word);
    }
    return true;
};